Relay



(No Model.)

P. E. CHAPMAN.

RELAY.

No. 558,672. Patented Apr. 21, 1896.

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UNITED STATES PATENT ()EEIcE.

FRANK E. CHAPMAN, OF MEDFORD, MASSACHUSETTS.

RELAY.

SPECIFICATION forming part Of Letters Patent NO. 558,672, dated April21, 1896.

Application filed January 27, 1896. Serial No. 576,958. (No model.)

To aZZ whom it may concern.-

Be it known that I, FRANK E. CHAPMAN, of Medford, in the county ofMiddlesex and State of Massachusetts, have invented certain new anduseful Improvements in Relays, of which the following is aspecification.

This invention has for its object the production of a novel and usefulrelay; and it consists in the novel features of construction andrelative arrangement of parts hereinafter fully described in thespecification, clearly illustrated in the drawings, and particularlypointed out in the claims.

Reference is to be had to the accompanying one sheet of drawings,forming a part of this application, in which like characters are used toindicate like parts wherever they occur.

Figure 1 represents in top plan view a relay constructed in accordancewith myinvention. Fig. 2 represents an end view thereof, the arms beingshown in section on the line 2 2 of Fig. 1, the electromagnets beingremoved.

The several elements of my relay may be variouslyarranged. I employ thecurrentin one winding of the inductioncoil to magnetize the armature andthe induced current of the secondary winding of the coil to move oroperate said armature.

Referring to the drawings, in the embodiment of my invention thereinshown and selected by me for the purpose of illustrating my invention, arepresents an inductiorrcoil, composed of a shell a made of soft iron,having a soft-iron head or end piece at one end. Secured to the closedend of this shell is a softiron core a. Electromagnets a" are connectedto one end of the core a of the induction-coil. As here shown, theseelectromagnets a are secured to arms a that project from the shell a andare thus connected to one end of the core a by means of said shell. Anarmature a is pivoted to the free end of said core by means of thescrews a passing through the cars a, Fig. 2, extending from the top andbottom of said shell. The free end of said armature vibrates between theopen poles a and a of the electromagnets a making contact with thescrews a and a, the local circuit 7L being connected to the armature andone screw a so as to be closed when the armature makes contact with saidscrew, screw a serving merely to regulate the play of said armature.

a represents a spring connected at one end to the armature and at theother end to the adj Listing-screw a carried by the arm a, Fig. 1. Thisspring serves to keep the armature to one side, opening the localcircuit 71. in the arrangement here shown, when no current is passingthrough the instrument or when not in operation.

1) represents the main or line circuit, of which b is the battery.

Z) represents the primary winding of the induction-coil, being connectedin circuit with the line b. The binding-posts (1 may be used, ifdesired, for connecting the primary winding Z) with the line-wire b inthe usual way.

f represents the secondary winding of the induction-coil. This windingis connected in circuit with the electromagnets a, the coils of saidelectromagnets being wound and connected in such manner that a currentpassing through them would make the adjacent ends a and a of oppositepolarity.

If now the main circuit 1) be closed, as ordinarily, by means of a key(not shown) located in said circuit, a current will be caused to flowthrough the primary winding b. The direction of the flow of said currentwill be dependent upon the polarity of the battery connected to theline. In this case, assuming it to be of the right polarity and passingthrough the primary winding Z) around the core a in such direction as tomake the armature end of said core a north pole and the end connected tothe shell a a south pole, the magnetism will continue through the closedend of said shell, through the shell itself to the open end, through thearms a and cores a of the electrom agnets, tending to make the adjacentends a and a of said cores of like polarity, in this case two southpoles. The armature a connected to the core a, and practically acontinuation of said core, will likewise be magnetized, the free end ofsaid armature becoming a north pole.

The main current passing through the primary coil 1), in addition to themagnetization just mentioned, will induce a momentary current in thesecondary winding f. This current passing through the coils of theelectro1nagnets a in a certain direction, as hereinbefore described, inthis case tends to make the end a of said electromagnet a a north pole,momentarily counteracting the magnetism from the primary coil beforedescribed, and thus decreasing the polarity at this point, Saidsecondary current also tends to make the end a of the electromagnet a" asouth pole. This magnetism, acting in conjunction with the magnetismfrom the primary coil hereinbefore described, momentarily makes said enda a south pole of increased strength. The armature a being north pole,is therefore drawn to the latter side, making contact with the screw aclosing the local circuit. The impulse of the secondary current nowhaving passed, the ends a" and a of the electromagnets a return to theprimarymagnetism equal strength south poles. The armature, however,being nearer the pole a moreforce is exerted on it from that side, whereit will remain, keeping the local circuit h closed, since the spring a,as stated below, has only suflicient tension to move the armature whenthere is no magnet-ism in the cores a. Now if the key on the main linebe opened, it stops the current flowing through the primary winding Z),induces a current of opposite polarity to the first in the secondarywinding f. This current, passing around the cores of the electromagnetsin the opposite direction, reverses in them the effect of the firstcurrent, now increasing the strength of the magnetism at the pole a",and counteracting the magnetism at the pole (0 the armature, not havinghad time to wholly demagnetize, will be drawn away from thecontact-screw a opening the local circuit h. The spring to, having onlysufficient tension to hold the armature when there is no magnetism inthe cores a, will now hold the armature against the stop a leaving thelocal circuit it open until the main line is closed again. If now themain-line currentbe reversed, and passing through the primary winding 7)of the relay in such direction as to make the armature end of the core aa south pole and the ends a an d a of the electromagnets ara north pole,the current induced by closing the key will be in the opposite directionfrom the current induced by closing the key in the case just mentioned,and will, therefore, have the reverse effect upon the cores of theelectromagnets a". Now the magnetism at the pole at will momentarilybecome strengthened and the primary magnetism at a will be counteracted.The armature consequently will be drawn toward the pole a making thecontact with the screw (0 and closing the local circuit 7b, the same asin the previous case. Now, by opening the key in the main circuit, theinduced current becomes reversed again, and reverses the effect at a anda as before described, the armature will be drawn to the stop a and heldthere by the spring a or by the residual magnetism remaining in thearmature or core a.

As from the nature of the induction-coils it is not necessary toabsolutely open and close the primary circuit, but simply increase ordecrease the current, to set up induced currents in the secondarycircuit, it will be seen that simply increasing and decreasing thecurrent on the main line, as on a leaky wire when a distant station istransmitting, will operate my relay, and, being once adjusted for aminimum, it will be operated by any heavier current that the wires withwhich its coils are wound are capable of carrying, the heavier currentsbeing only able to perform the same duty as the smaller by inducing asecondary current first in one direction when started or increased andin the opposite direction when stopped or decreased, throwing thearmature from side to side in exactly the same manner as the smallercurrent.

Having thus explained the nature of my invention and described a way ofconstructing and using the same, though without attempting to set forthall of the forms in which it may be made or all of the modes of its use,what I claim, and desire to secure by Letters Patent, is

1. A relay comprising in its construction, an induction-coil havingwindings in inductive relation, an armature, means whereby said armatureis magnetized by one of the windings of said coil, and means wherebysaid armature is operated by the other winding of said coil.

2. A relay, comprising in its construction, an induction-coil, twoelectromagnets connected to one end of the core of said coil, and incircuit with one winding of said coil, an armature connected to theother end of said core and arranged to be operated by saidelectromagnets, and to be magnetized by the other winding of said coil,as set forth.

An automatic relay, comprising in its construction, an induction-coil, ashell connected to the core of said coil, two electromagnets connectedto the shell of said coil, an armature pivoted to the core of said coil,the main circuit connected to one winding of said coil, the otherwinding of said coil being continued to form the winding of saidelectromagnets, and a local circuit controlled by said armature, as setforth.

4:. An automatic relay, comprising in its construction, aninduction-coil, a shell connected to the core of said coil, twoelectronnagnets connected to the shell of said coil,

an armature pivoted to the core of said coil, the main circuit connectedto the primary winding of said coil, the secondary winding of said coilbeing continued to form the winding of said eleetromagnets, a localcircuit controlled by said armature, and a spring for holding saidarmature to one side when there is no current in the primary winding, asset forth.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses, this 22d day of January, A. D.1896.

FRANK E. CHAPMAN. lVitncsses:

A. D. HARRISON, A. D. ADAMS.

